Heavy duty steel construction. Zinc plated and clear coated for added weather resistance. Very strong and can be used for a long time. The spring helps relieve stress from impacts, provides a more comfortable, softer feel, and will increase the life of your hammock, as well as your mounting surface. Compatible with almost all punching bags, punching bags, hanging chairs, cocoons, egg chairs, wicker chairs, etc. Rated spring capacity of over 700 lbs. Contents: 2 x carabiner. Wire Diameter: 7mm/0.3"(approx), Length: 108mm/4.25"(approx). 2pcs Heavy Duty Extension Carabiner Hanging Hook Accessories Swing Chairs Fishing Spring Bag for Hanging Chair Hammock And Swing. - Sturdy steel frame. Galvanized and transparent coating for greater resistance to atmospheric agents. - The spring helps relieve stress from impacts, provides a more comfortable, softer feel, and increases the life of your hammock, in addition to your mounting surface. - Rated spring capacity of over 700 lbs. - Suitable for almost any punching bag, hanging chair, cocoon, egg-shaped chair, wicker basket. Details: Item Name: Spring Hook Material: metal Quantity: 2 pieces Features: hammock accessories, durable, weather resistance Wire diameter: about 7mm/0.3" Length: 108mm/4.25"(Approx.) Package includes: 2 x garden swing springs